I wanted to tell you how impressed I have been this week with Nationwide. I bank online, but this week was not able to log in to my account using my card and card reader. Customer services, who were really helpful, explained my card had been blocked because of "unusual activity". In the week before Christmas, they had noticed payments on my debit card; all were in the US, none of which was mine.

We concluded that the fraud may have happened after I had used the Amazon US site to buy gifts for my son in Seattle, using the Amazon 1Click setting that is linked to that card.

Nationwide removed all the fraudulent payments from my account and sent me a new card which arrived in four days, despite the Christmas post. And in case I'd not checked my account online that day, they also sent me an alert by first-class mail asking me to contact them.

I am really bowled over by the speed with which they reacted – which while in their best interest was in mine, too. CRH Lymington, Hants

That is indeed good service. We experienced something similar recently, and while we were told that a replacement credit card would take several days to arrive, it came very quickly and there was minimal disruption. Your experience of having your account frozen, albeit temporarily, is why we always advise using a credit rather than debit card when paying for items bought online, particularly those abroad. You get far better consumer protection in the event of a problem, but, more importantly, if your details end up in the wrong hands and your account is frozen, it doesn't cripple your bank account.

Had you been on holiday and unable to access cash from the ATM network, you might not have been so happy.

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